Problem: What is the amplitude of $h(x)=-4\sin\left(2x-7\right)+3$ ?
Answer: Amplitude in sinusoids of the form $f(x)=a\sin(bx+c)+d$ The amplitude of a sinusoid of the form $f(x)={a}\sin(bx + c) + d$ is equal to $|{a}|$. [How can we justify this given our graphical understanding of amplitude?] Finding the amplitude The amplitude of $h(x)={-4}\sin\left(2x-7\right)+3$ is $|{-4}|=4$.